RG400 cable

Cable

RG400

RP-SMA FEMALE

End A

RP-SMA FEMALE

RP-SMA MALE

End B

RP-SMA MALE

Specs Summary

CableRG400
Diameter.195 INCH
Impedance50 Ohm
FrequencyDC – 6 GHz
Length25 ft
Velocity Factor70%
RP-SMA FEMALE InterfaceReverse polarity SMA threaded
RP-SMA MALE InterfaceReverse polarity SMA threaded
50 Ohm DC – 6 GHz

25 ft RG400 — RP-SMA FEMALE to RP-SMA MALE

RG400 cable assembly, 25 feet, with RP-SMA FEMALE and RP-SMA MALE connectors. Hand-assembled, tested, and ships free within the US.

25 ft — RP-SMA FEMALE / RP-SMA MALE

$80.88

Free shipping • In stock

Need a different length? Use the Cable Builder

Signal Loss — 25 ft

Approximate insertion loss for this 25 ft RG400 assembly at common RF frequencies.

Frequency Loss / 100 ft Loss — 25 ft
100 MHz 3.5 dB 0.88 dB
450 MHz 7.8 dB 1.95 dB
900 MHz 11.5 dB 2.88 dB
1.8 GHz 17 dB 4.25 dB
2.4 GHz 20 dB 5 dB
5.8 GHz 34 dB 8.5 dB

About This Assembly

RG400 Cable

RG-400 is a double-shielded, silver-plated PTFE coaxial cable built to MIL-C-17 specifications with a 0.195" outer diameter. Its construction mirrors RG-142 but with two braid shields for even greater shielding effectiveness. The standard cable for military and avionics applications requiring certified materials and traceable performance.

RP-SMA Connector

RP-SMA (Reverse Polarity SMA) uses the SMA threaded coupling mechanism but with the male/female pin convention reversed — the jack has a pin and the plug has a socket. Originally standardized to prevent connection of uncertified antennas to consumer WiFi equipment, RP-SMA is now the dominant connector on commercial WiFi routers, access points, and 2.4/5 GHz antennas.

Common Applications

This RP-SMA cable assembly is well suited for military-spec RF interconnects and avionics signal routing. The combination of reliable RP-SMA connectors and custom-cut cable length makes it a practical choice for both field installations and bench setups. Every assembly is hand-terminated, continuity tested, and ships free within the USA.

Frequently Asked Questions

Is this cable hand-assembled in the USA?

Yes. Every CoaxRF cable assembly is hand-terminated and continuity tested at our US facility before shipping. We do not drop-ship pre-made cables from overseas — each cable is built to order.

Can I order a different length than 25 ft?

Yes. This page is for the 25 ft assembly. Use the length buttons above to select a different standard length, or use the Cable Builder for any custom length.

How much signal loss will I see with this 25 ft cable?

At 1800 MHz, RG400 loses approximately 17 dB per 100 ft. This 25 ft assembly will have roughly 4.25 dB of insertion loss at that frequency. See the signal loss table for all frequency points.

What is the maximum frequency for this assembly?

This assembly is rated DC – 6 GHz. The effective frequency limit is set by the lowest-rated component — either the cable or one of the connectors. Both RP-SMA FEMALE and RP-SMA MALE connectors must be within spec at your target frequency.

What is your return policy?

We accept returns within 30 days of delivery. Custom-length cables are accepted as long as they are in original condition. Contact us and we will provide a prepaid return label at no charge.

Other RG400 Configurations